Bilingual Alzheimers patients do better than monolingual counterparts

Bilingual Alzheimer’s patients may have a better chance of delaying the onset of severe deterioration than their monolingual counterparts, according to new Canadian research, which could provide a ray of hope for large pockets of Canadian patients who have a handle on more than one language.

The study, published this week in the journal Cortex, used CT scans on the brains of 40 Alzheimer’s patients, half of whom were bilingual, and found those with more than one language had an increase in “cognitive reserve,” allowing them to keep more serious effects of the disease at bay for longer period of time.

“Obviously, this will be relevant to us Canadians,” said Tom Schweizer, one of the study’s authors and a neuroscientist at St. Michael’s Hospital in Toronto, noting Canada’s large population of bilingual residents. “It’s not that being bilingual is going to prevent Alzheimer’s from occurring . . . but being bilingual affords some type of ability that monolinguals don’t have to compensate for this disease process. Obviously the more people that have that, the better off we’ll be in terms of Alzheimer’s in the future.

“By having two languages and switching between one and another and suppressing one language in favour of another and constantly doing that over (a long period) of time, it had an effect on the cognitive networks in the brains, enhancing them some way.”

Schweizer said all the bilingual patients — who had an average age of about 79 — were able to speak two languages most of their lives and that second-language skills were not recently learned. He said it is unclear what effect newly acquired second-language skills would have in the fight to delay cognitive deterioration linked to the incurable disease.

According to the Alzheimer’s Society of Canada, more than half a million Canadians have dementia, with roughly 71,000 of those under the age of 65. In terms of Alzheimer’s specifically, 72 per cent of Canadian cases are women.

The organization estimated that within a generation, about 1.1 million Canadians will be living with some form of dementia.

Schweizer said researchers hope to expand on their findings by employing more detailed MRI scans to analyze bilingual and monolingual Alzheimer’s patients to evaluate the progression of the disease. While the CT scans used in the current study were helpful, they are considered a stepping stone to discovering more about disease progression.

He said that while other efforts to avoid a more rapid progression of Alzheimer’s are often used, the ability to switch between various languages is not much different.

“There’s other things that help to keep the mind sharp — crossword puzzles and sudoku, and things like that — and this is the same idea,” he said. “It suggests to keep the mind active to hopefully come up with some enhanced network pathways or connections to allow the brain to better deal with disease.

“We can say this lifelong bilingualism, which has been previously reported, is certainly a form of cognitive reserve, which is constantly doing mental activities . . . and that’s affording the bilingual (patients) some benefit and allowing them to compensate for a heavier disease burden.

“The more we can do to keep the mind active as we age, the better prepared the brain might be for dealing with disease and bilingualism is one form of that.”